"The database, first of its kind, will be complete by the end of this year," said Guo Xingping, director of Shanxi provincial population and Family Planning Commisssion Research Institute. Researchers are correlating data from 1,200 plus blood samples.

Shanxi has China's highest birth defect rate at around 1.9 percent with the national average level hovering around 1.3 percent. "Setting up of the database is just the start," said Wang Wanheng, a researcher.

The database will deepen knowledge and recognition of the relationship between disease and genes. The Shanxi samples are seen as highly representative and samples from other provinces and regions will be added to the database in the next five years, state-run news agency reported.

Birth defect refers to a physiological or structural abnormality that develops at or before birth. Neural tube defects, congenital heart disease, cleft lip and hydrocephalus are among the most common defects.

Birth defects are a serious problem in China, particularly in rural areas, and are the second-largest cause of infant death.

About nine lakh children are born with birth defects in China each year, accounting for 15 to 20 percent of affected newborns worldwide, the report said.